Terminal Blocks - Headers, Plugs and Sockets

Part Number	Description / PDF	Quantity
691358710005 Würth Elektronik Midcom	TERM BLOCK PLUG 5POS 5.08MM	0
691307400003 Würth Elektronik Midcom	7.62 MM TERMINAL BLOCK HEADER, V	249
691385700017 Würth Elektronik Midcom	5.00 MM TERMINAL BLOCK PLUG, HOR	24
691311700104 Würth Elektronik Midcom	TERM BLOCK HDR 4POS VERT 5MM	571
691361100008 Würth Elektronik Midcom	TERM BLOCK PLUG 8POS STR 3.5MM	649
691361100003 Würth Elektronik Midcom	TERM BLOCK PLUG 3POS STR 3.5MM	894
691701550012B Würth Elektronik Midcom	5.08 MM TERMINAL BLOCK HEADER, H	250
691308330005 Würth Elektronik Midcom	TERM BLOCK HDR 5POS VERT 3.81MM	0
691382030003 Würth Elektronik Midcom	TERM BLOCK HDR 3POS VERT 2.5MM	44
691386700009 Würth Elektronik Midcom	5.00 MM TERMINAL BLOCK HEADER, H	199
691311500012 Würth Elektronik Midcom	TERM BLOCK HDR 12POS VERT 5.08MM	355
691366310007 Würth Elektronik Midcom	3.81 MM TERMINAL BLOCK PLUG, HOR	299
691311500004 Würth Elektronik Midcom	TERM BLOCK HDR 4POS VERT 5.08MM	341
691365110005 Würth Elektronik Midcom	3.50 MM TERMINAL BLOCK PLUG, HOR	314
691353500017 Würth Elektronik Midcom	5.08 MM TERMINAL BLOCK PLUG, VER	15
691325110004 Würth Elektronik Midcom	3.50 MM TERMINAL BLOCK HEADER, H	278
691309510012 Würth Elektronik Midcom	5.08 MM TERMINAL BLOCK HEADER, H	33
691352510009 Würth Elektronik Midcom	TERM BLOCK PLUG 9POS 5.08MM	115
691364100007 Würth Elektronik Midcom	3.50 MM TERMINAL BLOCK PLUG, VER	275
691349340003 Würth Elektronik Midcom	TERM BLOCK PLUG 3POS STR 3.81MM	95

Terminal Blocks - Headers, Plugs and Sockets

1. Overview

Terminal blocks, headers, plugs, and sockets are essential components in electrical and electronic systems for establishing reliable connections between circuits. These devices enable signal transmission, power distribution, and system modularity. Their standardized designs ensure interoperability, scalability, and ease of maintenance in complex systems.

2. Main Types and Functional Classification

Type	Functional Characteristics	Application Examples
Terminal Blocks	Screw/clamp-based connections for high current/ voltage	Industrial control panels, power distribution units
PCB Headers	Pin/grid arrays for board-to-board connections	Embedded systems, Arduino shields
RJ Connectors	Modular jacks for data/telecom signals	Ethernet networks (RJ45), telephone systems (RJ11)
D-Sub Connectors	Multi-pin trapezoidal shells for analog/digital signals	Legacy serial interfaces, industrial sensors
USB Connectors	Hot-pluggable interfaces for power/data	Consumer electronics, peripheral devices

3. Structure and Components

Typical structures include:

Insulating housing (PA66, PBT, or LCP plastics)
Contact elements (phosphor bronze, beryllium copper)
Plating materials (gold, tin, nickel for corrosion resistance)
Actuation mechanisms (screws, spring clamps, or friction fits)
EMI shielding layers (for high-frequency applications)

4. Key Technical Specifications

Parameter	Importance
Current Rating (A)	Determines power handling capacity
Voltage Rating (V)	Defines dielectric strength requirements
Contact Resistance (m )	Impacts signal integrity and power loss
Insertion Loss (dB)	Critical for high-speed data transmission
Mating Cycles	Indicates mechanical durability
Operating Temperature (- C to + C)	Defines environmental tolerance

5. Application Fields

Primary industries include:

Industrial automation (PLCs, HMIs)
Telecommunications (5G base stations, routers)
Consumer electronics (smartphones, wearables)
Medical equipment (imaging devices, patient monitors)
Automotive (EV charging systems, ADAS)

6. Leading Manufacturers and Products

Manufacturer	Representative Product
Phoenix Contact	COMBICON series terminal blocks
TE Connectivity	MICRO MATCH connectors
Molex	SL Series headers
Amphenol	D-Subminiature connectors
Samtec	QTE high-speed socket systems

7. Selection Guidelines

Key considerations:

Electrical requirements (current/voltage levels)
Mechanical constraints (space, vibration)
Environmental factors (temperature, humidity)
Signal integrity needs (frequency, noise rejection)
Cost vs. reliability trade-offs
Compliance with standards (IPC, IEC, UL)

8. Industry Trends

Emerging developments include:

Miniaturization for wearable devices
High-speed connectors for 5G/6G ( 25 Gbps)
Hybrid connectors integrating power/data
Eco-friendly materials (halogen-free, RoHS compliant)
Smart connectors with built-in sensors
Automotive-grade connectors for EVs